First stab at modular screen saver support
diff --git a/contiki-c64/apps/ssfire.c b/contiki-c64/apps/ssfire.c
new file mode 100644
index 0000000..ee61ab6
--- /dev/null
+++ b/contiki-c64/apps/ssfire.c
@@ -0,0 +1,188 @@
+/*
+ * Copyright (c) 2002, Adam Dunkels.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials provided
+ * with the distribution.
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgement:
+ * This product includes software developed by Adam Dunkels.
+ * 4. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This file is part of the Contiki desktop environment
+ *
+ * $Id: ssfire.c,v 1.1 2003/04/24 17:10:34 adamdunkels Exp $
+ *
+ */
+
+#include <stdlib.h>
+
+#include "ctk.h"
+#include "ctk-draw.h"
+#include "dispatcher.h"
+#include "loader.h"
+
+static unsigned char save;
+
+static DISPATCHER_SIGHANDLER(ssfire_sighandler, s, data);
+static void ssfire_idle(void);
+static struct dispatcher_proc p =
+ {DISPATCHER_PROC("Fire screensaver", ssfire_idle,
+ ssfire_sighandler,
+ NULL)};
+static ek_id_t id;
+
+
+static unsigned char flames[8*17];
+
+static unsigned char *flameptr, *colorptr1, *colorptr2;
+static unsigned char x, y;
+
+
+static const unsigned char flamecolors[16] =
+ {COLOR_BLACK, COLOR_BLACK, COLOR_BLACK,
+ COLOR_RED, COLOR_LIGHTRED, COLOR_YELLOW, COLOR_WHITE,
+ COLOR_WHITE, COLOR_WHITE, COLOR_WHITE, COLOR_WHITE,
+ COLOR_WHITE, COLOR_WHITE, COLOR_WHITE, COLOR_WHITE,
+ COLOR_WHITE};
+
+
+
+/*-----------------------------------------------------------------------------------*/
+LOADER_INIT_FUNC(ssfire_init)
+{
+ if(id == EK_ID_NONE) {
+ id = dispatcher_start(&p);
+ dispatcher_listen(ctk_signal_screensaver_start);
+ dispatcher_listen(ctk_signal_screensaver_stop);
+ dispatcher_listen(ctk_signal_screensaver_uninstall);
+ }
+}
+/*-----------------------------------------------------------------------------------*/
+static void
+fire_quit(void)
+{
+ dispatcher_exit(&p);
+ id = EK_ID_NONE;
+ LOADER_UNLOAD();
+}
+/*-----------------------------------------------------------------------------------*/
+static void
+fire_init(void)
+{
+ unsigned char *ptr, *cptr;
+
+ SID.v3.freq = 0xffff;
+ SID.v3.ctrl = 0x80;
+ SID.amp = 0;
+
+ VIC.ctrl1 = 0x1b; /* $D011 */
+ VIC.addr = 0x17; /* $D018 */
+ VIC.ctrl2 = 0xc8; /* $D016 */
+ VIC.bordercolor = 0x00; /* $D020 */
+ VIC.bgcolor0 = 0x00; /* $D021 */
+ CIA2.pra = 0x03; /* $DD00 */
+
+ /* Fill screen with inverted spaces. */
+ cptr = COLOR_RAM;
+ for(ptr = (unsigned char *)0x0400;
+ ptr != (unsigned char *)0x07e8;
+ ++ptr) {
+ *ptr = 0xa0;
+ *cptr++ = 0x00;
+ }
+}
+/*-----------------------------------------------------------------------------------*/
+static
+DISPATCHER_SIGHANDLER(ssfire_sighandler, s, data)
+{
+ DISPATCHER_SIGHANDLER_ARGS(s, data);
+
+ if(s == ctk_signal_screensaver_start) {
+ fire_init();
+ save = 1;
+ } else if(s == ctk_signal_screensaver_stop) {
+ save = 0;
+ ctk_draw_init();
+ ctk_redraw();
+ } else if(s == ctk_signal_screensaver_uninstall) {
+ fire_quit();
+ ctk_draw_init();
+ ctk_redraw();
+ }
+}
+/*-----------------------------------------------------------------------------------*/
+void
+ssfire_idle(void)
+{
+ if(save) {
+
+ /* Calculate new flames. */
+ asm("ldx #0");
+ asm("loop:");
+ asm("lda _flames+7,x");
+ asm("clc");
+ asm("adc _flames+8,x");
+ asm("adc _flames+9,x");
+ asm("adc _flames+16,x");
+ asm("lsr");
+ asm("lsr");
+ asm("sta _flames,x");
+ asm("inx");
+ asm("cpx #(8*15)");
+ asm("bne loop");
+
+ /* Fill last line with pseudo-random data from noise generator on
+ voice 3. */
+ asm("ldx #$05");
+ asm("loop2:");
+ asm("ldy #$20");
+ asm("delay:");
+ asm("dey");
+ asm("bne delay");
+ asm("lda $d41b");
+ asm("and #$0f");
+ asm("sta _flames+8*15+1,x");
+ asm("dex");
+ asm("bpl loop2");
+
+ /* Display flames on screen. */
+ flameptr = flames;
+ colorptr1 = COLOR_RAM + 40*10;
+ colorptr2 = colorptr1 + 0x20;
+ for(y = 0; y < 15; ++y) {
+ for(x = 0; x < 8; ++x) {
+ *colorptr1 = *colorptr2 = flamecolors[*flameptr++];
+ ++colorptr1;
+ ++colorptr2;
+ }
+ colorptr1 += 0x20;
+ colorptr2 += 0x20;
+ }
+
+ }
+}
+/*-----------------------------------------------------------------------------------*/
+
+/*-----------------------------------------------------------------------------------*/